Would Denver or Boulder have been included in this area? What about areas further west such as Aspen and Vail? Are there any accurate maps that show exactly what areas in Colorado were ceded in this treaty?
This was the actual map used during the treaty negotiations. By recognizing the annexation of Texas, and giving up the last strip in the west, Mexico ceded claims to about half of what is now the state of Colorado.
[Here's a larger map)(http://www.thomaslegion.net/sitebuildercontent/sitebuilderpictures/usexpansionmexicancessionmaphistory.jpg).
As you can see, Grand Junction is the largest city ceded by the Treaty of Guadalupe Hidalgo, although the Arkansas River which flows through the middle of Pueblo, Colorado, was once the border between the United States and Mexico (and later the Republic of Texas).
